Degenerative Lumbar Disc Disease in the Mature Athlete Treatment & Management

Rehabilitation Program

Physical Therapy

During the acute phase of a rehabilitation program for discogenic LBP, the focus of treatment is on reducing pain symptoms. Instruction in posture and body mechanics in activities of daily living is aimed at protecting injured structures, reducing symptoms, and preventing further injury. Educate patients to avoid positions that increase intradiscal pressure, such as sitting, bending, and lifting. A short course of bed rest (1-2 d) may provide some beneficial effects via pain modulation and reduction of intradiscal pressure, but longer courses of bed rest yield detrimental effects on bone, connective tissue, muscle, and cardiovascular fitness.

Emphasis on activity modification, rather than strict bed rest, is recommended to avoid the unwanted effects of immobilization.

Modalities, such as electrical stimulation, should be limited to the initial stages of treatment so that patients can quickly progress to more active treatment that includes restoration of motion and strengthening. Electrical stimulation can be combined with ice to enhance its analgesic effect.

Surgical Intervention

Surgical consultation is warranted in patients with acute discogenic back or leg pain when there is progressive neurologic loss. Large midline disc protrusions with cauda equina syndrome, characterized by saddle anesthesia (ie, perineal numbness) and bowel or bladder dysfunction, require urgent surgical decompression. Other indications for surgical intervention are less clear-cut. No data show that operative intervention restores neurologic function more rapidly than nonoperative treatment. Saal, in his description of the natural history of lumbar disc herniation, notes that patients who recover without surgery usually demonstrate signs of improvement in the first 3-6 weeks from the time of onset.^[4] Many authors suggest that it is reasonable to operate on patients with significant neurologic loss (eg, a foot drop) that has not improved by 6 weeks postinjury.

Other Treatment

Lumbar epidural steroid injections (LESIs) have been used to treat a variety of low back conditions. Controlled studies have evaluated the effectiveness of epidurals in the treatment of lumbar conditions, with some studies showing success in certain subgroups of patients with discogenic back pain.

A study by Lutz showed a success rate of 75.4% using selective nerve blocks in conjunction with oral medications and physical therapy for the treatment of acute herniated discs. Most controlled and uncontrolled studies indicate that LESIs provide short-term benefits for patients with lumbar radiculopathy and can be an important component to an overall treatment approach. Meta-analyses have failed to show a long-term benefit from these injections.

A randomized, controlled trial by Khot et al demonstrated that intradiscal steroid injections compared with saline injections (control group) in men with spinal discogenic pain did not improve the clinical outcome in pain reduction.^[7] The mean age of these patients was approximately 43 years. In a prospective trial by Butterman comparing LESIs to discectomy for lumbar disc herniation, 42-56% of the 50 patients randomized to LESI reported successful outcomes. Another study by Butterman showed LESIs to be effective, specifically in patients with advanced DDD and those with MRI findings of discogenic inflammation and adjacent end-plate changes.^{[8, 9]}

Nonradicular pain has been shown to be predictive of poor treatment response rates; therefore, LESIs typically are reserved for patients with radicular features. Mature athletes with DDD who have localized axial pain are not appropriate candidates for these injections. Individuals with radicular features as their presenting clinical symptom may benefit from an epidural injection to allow facilitation of a comprehensive rehabilitation program. However, in older populations, radiculopathy is more likely to result from spinal stenosis (spina canal or foramina), and epidural injections have not been found to be nearly as effective in cases of radiculopathy secondary to abnormal bone structure compared with radiculopathy secondary to disc herniation. Therefore, the role of LESIs in the mature athlete with DDD appears to be limited. Furthermore, most studies indicate that LESI is most likely to be successful in patients who have had symptoms for less than 6 months.

Overall, more investigations of LESIs are needed to firmly establish the population best served by this treatment. Randomized, controlled trials are needed, given the poor design of many existing studies, with no control groups, heterogeneous populations, and injections performed without fluoroscopic guidance.

Rehabilitation Program

Physical Therapy

Once the painful symptoms are controlled during the acute phase of treatment, strengthening exercises for the lumbar spine and associated muscles can be initiated. The clinical presentation of DDD in the mature athlete can be quite variable; therefore, no single group of exercises can treat all patients effectively.

The McKenzie exercise approach to disc pathology does not commit to either flexion or extension activities, but rather it identifies postures and motions that centralize referred LBP. The McKenzie program is initiated only after a comprehensive assessment determines which positions most effectively centralize a patient's pain. These exercises eventually are incorporated into a more comprehensive spinal rehabilitation program that includes spine stabilization exercises.

In spine stabilization exercises, the goal is to teach the patient how to find and maintain a neutral spine during everyday activities. The neutral spine position is specific to the individual and is determined by the pelvic and spine posture that places the least stress on the elements of the spine and supporting structures. In classic discogenic pain, the neutral spine has an extension bias. In classic posterior element pain or spinal stenosis, which may both result from the ongoing degenerative cascade initiated by disc degeneration, the neutral spine may have a mild flexion bias. Dynamic lumbar stabilization may be used with the McKenzie approach to provide dynamic muscular control and to protect the spine from biomechanical stresses including tension, compression, torsion, and shear. Spinal stabilization provides this control and protection by emphasizing the synergistic activation of the trunk and spinal musculature in the midrange position.

Strengthening of the abdominal and gluteal muscle groups is stressed because these muscles form part of the dynamic stabilizers of the spine and attach to the thoracolumbar fascial support system, one of the potential spine stabilizing structures. Spine stabilization exercises lend themselves to the mature athlete because the overall goals of this comprehensive exercise program are to reduce pain, to develop the muscular support of the trunk and spine, and ultimately to diminish the overall stress to the intervertebral disc and other static stabilizers of the spine.

In addition to specific spine stabilization concepts, the spine should also be assessed in conjunction with the entire kinetic chain to which it is linked. Restrictions or weaknesses in one part of the chain can manifest as problems in another region. For example, restrictions in hip ROM can lead to increased stresses on the lumbar spine during certain activities (eg, golfing), increasing the chance for dysfunction and injury. Therefore, elements of the entire kinetic chain should be targeted as part of a comprehensive rehabilitation program.

Mature athletes with DDD of the spine should have lower-extremity closed-kinetic chain exercises incorporated into their therapy regimens. These exercises also should be included in the regimen for those who participate in activities involving the upper extremities, since a great deal of the force generated in overhead sports occurs in the trunk and lower extremities. In athletes who participate in activities involving the upper extremities and who have LBP, both upper- and lower-extremity closed-kinetic chain exercises should be included in the rehabilitation program.

Rehabilitation Program

Physical Therapy

The maintenance phase represents the final phase of the rehabilitation process. Eccentric muscle strengthening exercises, including more dynamic conditioning exercises (eg, with a large gym ball), are added to the program. In addition, sport-specific training should be incorporated so that the mature athlete can maintain a neutral spine in all recreational activities.

The goals of a comprehensive spinal rehabilitation program have been met when the mature athlete no longer demonstrates the original symptoms, full ROM of the spine is present, strength and flexibility are within normal limits, and good sport-specific mechanics are demonstrated.

Surgical Intervention

Lumbar fusion

A general lack of consensus exists regarding the indications for lumbar fusion in patients with degenerative disc disease (DDD). The natural history of DDD has not been shown in scientific studies to be treatable with great success by any method of lumbar fusion.

An Cochrane review of surgical interventions for degenerative lumbar disease found inconclusive results for a firm conclusion on the effectiveness of fusion surgery.^[10] Two randomized clinical trials compared spinal fusion with conservative treatment: a Swedish trial reported by Fritzell et al found that patients who underwent surgery had significant improvements in pain and significantly higher rates of return to work^[11] ; the second trial, a Norwegian trial reported by Brox et al and Keller et al found no significant differences in outcomes in surgery compared with a conservative rehabilitation approach.^{[12, 13]}

A significant morbidity associated with lumbar fusions involves juxtafusional degeneration, which may require reoperation within approximately 10 years of a successful fusion surgery. Some studies have suggested hastening of degeneration of spinal functional units adjacent to the fused vertebrae. Furthermore, fusion causes limited range of motion, a consequence that has become less acceptable as a treatment outcome.

Disc arthroplasty

A developing alternative to lumbar fusion surgery emerging in modern medicine is total lumbar disc replacement surgery, also known as disc arthroplasty. The desire for this approach to degenerative lumbar disc disease is to treat low back pain while avoiding the limitations of surgical fusion, including limitations in ROM and segmental instability or degeneration of adjacent spinal segments. Candidates for disc arthroplasty are limited to patients without significant facet joint dysfunction because this has been associated with poor outcomes.

Disc replacement devices continue to undergo investigative trials. The Charite artificial disc, which is commercially available in the United States and has been limited to disease of L4-L5 or L5-S1. European data with complication rates of lumbar disc arthroplasty give pause to the use of this intervention, as does the overall limited long-term follow-up and randomized clinical trials currently available. Furthermore, the average age of patients who are candidates for total disc replacement are typically younger than those who are candidates for total joint replacements, further highlighting the need for longevity of the implanted devices.

To the authors’ knowledge, the medical literature does not yet provide enough data to support or refute firm conclusions on the safety and applicability of disc arthroplasty in the mature athlete.

Nucleus pulposus replacement

An emerging technology is nucleus pulposus replacement. This surgical intervention is designed to increase disc space height in the degenerating disc and decrease the transmission of forces onto the remaining annulus, facet joints, and other stabilizing structures. Compared with total disc replacement, this surgical option involves less surgical exposure, potentially provides biomechanics similar to native discs, and the advantage that a failure of nucleus pulposus replacement still allows for revision with fusion if necessary. The implants currently under investigation are primarily composed of hydrogels that an absorb water and release water when loaded.

Limitations in implant materials include toxicity of the materials and the danger of their extrusion from the disc space. One such implant with the most thorough studies yet is the Prosthetic Disc Nucleus, which is designed to absorb 80% of its weight in water. It has been shown in a small study by Schonmayr et al to restore disc space height and normal motion.

Other Treatment

Intradiscal electrothermal therapy (IDET) involves the insertion of an electrothermal catheter into a painful intervertebral disc under fluoroscopic guidance. Thermal energy delivered by the catheter results in breakdown and restructuring of collagen fibers in the annulus. Several mechanisms by which IDET might relieve discogenic pain have been proposed, including an alteration of annular tears, stiffening of the intervertebral disc, or simple ablation of nerve endings in the annulus.

Proponents of the procedure believe that IDET may be indicated for patients who have degenerative disc changes with concordant pain on discography and a chronicity of LBP for all conservative management techniques have failed. A preliminary nonrandomized study by Saal and Saal on a small number of patients who had IDET revealed an improvement in function by a visual analog scale and sitting tolerance time.^[4]

Two randomized clinical trials demonstrated extremely poor results,^{[14, 15]} but a trial by Pauza et al reported significant improvement in pain; however, this last study was conducted on a highly select group of patients.^[16] A prospective trial, by Park et al, in Korea showed that 84% of the 25 patients enrolled had persistence of pain and, overall, reported poor satisfaction after IDET.^[17] The trials for IDET have been small, and few have rendered applicability and firm conclusions.